Dylib error on catalina but not Mojave or Big Sur

I’m trying to test an application i’m working on, but getting the following error when I try to run it in the debugger, on my mac at home (running Catalina). I don’t get this error on Mojave or Big Sur on two machines at work. The dylib in question is one that we had someone port from a windows DLL.

When I go to System Preferences/Security & Privacy/General, I get the usual warning about it being from an unidentified developer, and I click on Open Anyway. But at this point the debugger throws an error because It couldn’t find the library, and even after I’ve allowed it in the system prefs, I get this every time I run the program for testing in the debugger.

Is this a problem specific to catalina? Because I’m not seeing the same behavior with the same application on Mojave or Big Sur.

Please put back system preferences.

Second, the dmg with the dylib is not notarized.
If you still trust the source and think it is not malware, you can use Terminal commands to remove quarantine with “xattr -cr” command line tool.

Thanks. It’s not a DMG, it’s just a zip package that was extracted and copied, but I’m gathering that’s the same thing as far as the OS is concerned. The developer said as much just now, in an email. I’ll try to remove the quarantine tonight, when I’m back home where my laptop is.